The present disclosure relates to delivering water of optimal microbiologic quality, and more particularly to a portable system, device, and method that neutralizes calcium, magnesium, and pathogenic contaminants in dental waterlines.
All sources of water possess naturally occurring contaminants. As water is a universal solvent, many minerals and pathogenic microorganisms directly contaminate water supplies. Low level exposure to these contaminants pose little risk to water quality and their removal does not always provide greater health protection. However, documented outbreaks of waterborne disease and reports of waterborne infection from municipal water supplies illustrate the growing threat of contaminated drinking water.
The standard of dental care concerning infection control has long focused on hygienic practices including the effective sterilization of dental handpieces, turbines, water syringes, and intraoral devices. In the past, dental waterlines were frequently overlooked when planning effective infection control. As there were few reported adverse health effects to dental water exposure, there was little evidence of a public health risk. In 1993, the Centers for Disease Control and Prevention (CDC) recognized the microbiologic quality of water used in dental treatment could be improved. Accordingly, the CDC recommended a number of infection control practices to be followed in dental operatories. A routine practice of flushing waterlines continuously at the beginning of each clinical day was recommended to substantially reduce microbial accumulations. Sterile saline and sterile water purges were also recommended practices. However, active adhesion of pathogenetic microorganisms to polyvinylchloride and the inadequate maintenance of sterile saline and sterile water supplies allow some pathogens to survive in spite of these preventive practices.
A commonly followed practice for controlling waterline contamination in dental units has been to install independent water systems. These systems allow delivery of sterile water effectively eliminating the threat of municipal water micro-contamination. Dental waterlines, however, have shown that heterotrophic bacteria, fungi, and protozoans can survive in sterile water. The colonization and replication of these microorganisms result in microbial accumulations, known as biofilms. Prolonged exposure to the interior surfaces of waterlines result in adhesion, microbial multiplication, and ensuing colonization. Biofilms are generally asymmetrically distributed and are known to associate in microcolonies. Some systems attempt to eliminate biofilm colonies by improving the water supplied to dental unit. These systems are not always effective because once biofilms form they reproduce.
Scale buildup occurs when dissolved minerals suspended in water precipitate or fall out of their suspended state. The storing of water in dental units can cause scale buildup which is a concentration of calcium and magnesium attaching to waterlines, fittings, valves, and sensors. Calcium and magnesium scales reduce the cleaning and disinfecting performance of many germicidal agents thereby requiring the use of stronger chemical mixtures to attain uncertain results. To that end, hard water left untreated may cost practitioners higher operating costs, restricted water flow, reduced water pressure, and poor water quality even when an aggressive water quality control program is followed.
Practitioners following conventional practice may install water softeners that remove calcium and magnesium minerals from water to their disinfecting systems. For every calcium and magnesium ion removed, conventional water softeners add two salt ions which do not interfere with the disinfecting process. Softened water, however, is not always recommended for consumption and therefore, secondary systems such as filtration systems may be needed to remove sodium or other harmful media as part of the unique nature of patient care. The addition of a filtration system further increases the cost and maintenance of conventional disinfecting systems and may provide a breeding surface for bacteria if not properly maintained.
Another practice for controlling waterline contamination in dental units is the use of micro-filtration systems exclusively. These systems attempt to suppress bacterial contaminants by filtering water primarily at a point-of-entry to the dental unit. The filters, however, do not treat waterlines up and to the waters point-of-use and like conventional filters may provide a breeding surface for biofilm growth.
In other conventional systems, the dental waterlines are periodically or continuously flushed with a disinfecting agent. These processes do not always eliminate bacterial contamination as scale, may isolate the disinfectant allowing subsequent waterline contamination, and create an environment that promotes bacterial resistance to the disinfectant. A periodic or continuous use of the disinfectant, therefore, may pose a risk to the dental patient if all contamination including scale deposit is not first removed.
As the focus shifts to reducing the risk of disease transmissions in all aspects of dental practice, an effective infection control system for decontaminating dental waterlines is needed. As the ADA expressed in its Dec. 13, 1995, Statement on Dental Waterlines, there is a need to improve dental waterline quality.